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This is based on the fact that a reciprocal lattice vector (the vector indicating a reciprocal lattice point from the reciprocal lattice origin) is the wavevector of a plane wave in the Fourier series of a spatial function (e.g., electronic density function) which periodicity follows the original Bravais lattice, so wavefronts of the plane wave ...
Unit cell of an fcc material. Lattice configuration of the close packed slip plane in an fcc material. The arrow represents the Burgers vector in this dislocation glide system. Slip in face centered cubic (fcc) crystals occurs along the close packed plane. Specifically, the slip plane is of type , and the direction is of type < 1 10>.
[4] [5] The bcc and fcc, with their higher densities, are both quite common in nature. Examples of bcc include iron, chromium, tungsten, and niobium. Examples of fcc include aluminium, copper, gold and silver. Another important cubic crystal structure is the diamond cubic structure, which can appear in carbon, silicon, germanium, and tin.
The FCC and HCP packings are the densest known packings of equal spheres with the highest symmetry (smallest repeat units). Denser sphere packings are known, but they involve unequal sphere packing. A packing density of 1, filling space completely, requires non-spherical shapes, such as honeycombs.
Figure 6. Surface diffusion jump mechanisms. Diagram of various jumps that may take place on a square lattice such as the fcc (100) plane. 1) Pink atom shown making jumps of various length to locations 2-5; 6) Green atom makes diagonal jump to location 7; 8) Grey atom makes rebound jump (atom ends up in same place it started).
A stacking fault is an irregularity in the planar stacking sequence of atoms in a crystal – in FCC metals the normal stacking sequence is ABCABC etc., but if a stacking fault is introduced it may introduce an irregularity such as ABCBCABC into the normal stacking sequence. These irregularities carry a certain energy which is called the ...
The surface tension of an interface thus varies according to the density on the surface. Dense crystallographic planes. Microstructural defects: Pores and crystallites tend to have straight grain boundaries following higher density planes. Cleavage: This typically occurs preferentially parallel to higher density planes.
The FCC lattice is a Bravais lattice, ... (planar) lattice. ... is the probability density function for the separation ...